PHP include call used to work, doesn't now, and my ISP blames me...help?

Question

Hello all,
Here's the deal: I have a website, www.website.com which has a sub-domain, subdomain.website.com. I use one CSS file for both sites, the subdomain calls to the main website. Likewise, I pull graphics from the main site that appear on the subdomain. Everything works swimmingly.
I also have a navbar that is common to both sites. For simplicity, the navbar is in an includes folder in the main site's root directory. I do this so that changes made to the navbar can be instantaneous across both sites. I avoid having to upload includes files to BOTH sites every time I change one of them. Here's how I call it in the code:
<?php include('http://www.website.com/includes/navbar2.php'); ?>
This USED TO WORK JUST FINE. Not long ago, pages in the subdomain are no longer able to call the navbar from the includes folder on the main site. I get three <function include> errors where there ought to be the navbar. I contacted my ISP (Network Solutions) and they blame it on 'custom coding' which is absurd as I haven't altered the code on these pages in months...far before the problem occurred.
Here is the html for the three <function include> errors:
<b>Warning</b>:  include() [<a href='function.include'>function.include</a>]: URL file-access is disabled in the server configuration in <b>/(actual path info removed)/main.php</b> on line <b>31</b><br />
<br />
<b>Warning</b>:  include(http://www.website.com/includes/navbar2.php) [<a href='function.include'>function.include</a>]: failed to open stream: no suitable wrapper could be found in <b>/(actual path info removed)/main.php</b> on line <b>31</b><br />
<br />
<b>Warning</b>:  include() [<a href='function.include'>function.include</a>]: Failed opening 'http://www.website.com/includes/navbar2.php' for inclusion (include_path='.:/usr/services/vux/lib/php') in <b>/(actual path info removed)/htdocs/subdomain_folder/main.php</b> on line <b>31</b><br />
I think it's a server-side change. Has to be as I have not altered the code at all in ages. Any thoughts, suggestions or help would be very much appreciated.
Sincerely,
wordman

Answer 1

Wordman-GL wrote:
Here's how I call it in the code:
<?php include('http://www.website.com/includes/navbar2.php'); ?>
This USED TO WORK JUST FINE.
Your hosting company is quite correct in blaming you, although it should probably have explained why it no longer works.
Since PHP 5.2, there have been two security directives: allow_url_fopen, which is on by default, and allow_url_include, which is off by default.
Including a file directly from a URL is a major security risk, which is why allow_url_include is turned off. If you want to include content from a URL, you must retrieve it using a file function, such as file_get_contents(), and run your own security checks on it before including it in a page.